#52 Warren Buffett

Multi-billionaire Warren Buffett, 85, is the most successful investor of the 20th century, but the Nebraskan native is also a generous philanthropist. In 2006, he announced his intention to give away his fortune to charity, with 83 per cent of it going to the Bill & Melinda Gates Foundation. In 2010, Buffett, Bill Gates and Mark Zuckerberg, signed the “Gates-Buffett Giving Pledge”, to donate at least half their wealth. Buffett’s Berkshire Hathaway company has also thrown its weight behind renewable energy efforts. Buffett has always been a vocal advocate of sustainable economic growth.